Transmission and control mechanism therefor



Jan. 5, 1954 D. w. KELBEL 2,554,765

l TRANSMISSION AND CONTROL MECHANISM THEREFOR Filed June 9, 1944 l2 Sheets-Sheet l %N .$1 QN A u NN .QN l l i ,W D Q WI) q q w kwwww f L A 1 ,www ww u?, ww, 7 l w .t "JVE y. mwmmwv 7 f D. w. KELBEL. TRANSMISSION AND CONTROL MECHANISM THEREF'OR Jan. 5, 1954 Filed June 9, 1944 2 Sheets-Sheet 2 vLOl I NWN? r l l Patented Jan. 5, 1954 TRANSMISSION AND CONTROL MEoHANIsM THEREFOR Donald W; Kelbel, Muncieylnd., assigner to Borg- Warner Corporation, Chicago, Ill., a corporation of Illinois My invention relates to transmissions and control arrangements therefor and more particularly to such apparatus which is suitable for use in a motor driven Vehicle. ,l u

` lt is an object of my invention to provide an improved transmission which provides a plurality of speed ratios and which is such that it shifts easily between the speed ratios. More particularly it is an object to provide an improved transmission which comprises a planetary gear set including sun, ring and planet gears, a one-way brake for an element of the gearing whereby the gearing provides a low speed ratio drive through the transmission, and a fluid coupling connected between the driven shaft of the transmission and an element of the planetary gearing for substantially locking up the gearing when the speed of the driven shaft has increased sufficiently whereby to provide a high speed ratio through the transmission. It is a further object of my invention to provide an improved transmission of this type which is such that a reverse drive may facilely be obtained through the transmission.

It is another object of my invention to provide an improved control arrangement for a transmission of this type which is such that the transmission may be easily downshifted from high speed ratio to low speed ratio under the control of the accelerator for the motor vehicle in which the transmission is installed. More particularly it is an object of my invention to provide in a transmission of this type a fluid coupling which has .a discharge outlet in its casing for allowing a steady discharge of iluid out of the coupling, a pump for supplying uid to the coupling to render it operative and a valve eifectively between the pump and the fluid coupling under the control of the accelerator which functions to effectively disconnect the pump with respect to the fluid coupling when the accelerator is moved to its open throttle position so that the fluid coupling drains off uiol and is made ineffective whereby the low speed ratio becomes effective through the transmission.

The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above stated objects and such other objects as will appear from the following description of a Acertain preferred embodiment illustrated in the Application June 9, 1944, serial No. 539,443 .is Claims. (o1. 'f4- 645) Fig. 4 is a diagrammatic illustration of a control varrangement which may be used with either of the transmissions shown in Figs. 1 to 3.

Like characters of reference designate like parts in the several views.

nReferringnow to the drawings, the transmission illustrated in Figs. l and 2 comprises a drive shaft I0, aY driven shaft II, and an intermediate `shaft I2 which is piloted in both of the shafts II andvII. The drive `shaft IIl is connected with a centrifugal clutch I3, and the latter includes a Viiy-wheellfl bolted to the shaft I (i which is of the ordinary type usedfin automotive vehicles. A casing portion l5 is xed Yto the ily wheel I4, and va pressure plate I6 is disposed within the casing portion and is non-rotatably xed with respect to the casing portion by means of tongues 'Il' on'the pressure plate extending through slots I8 in the casing portion andl by means of studs I9 fixed' with' respect to the pressure plate and extending through the casing portion. A disc-like member 26 is disposedwithin the casing portion I5 and is caused to rotate with the casing portion by the studsv I9 extending through the member 20 and by means of Vother studs 2I carried by Ythe member 2!) and fixed to the casing portion.

.Springs-22 are disposed on the studs I9 and extend between the disc-like member 20 and collars 23y on the studs I9, and these springs function to'yieldingly hold the pressure plate I6 at the limit of its movement away from the fly-wheel It.

, Governor weights 2L! are disposed within the disclikemember 23 and have stem portions 25 eX- te'ndin'g'through the member 20 and into the pressure plate I6, and these stems are of such shape that they bear against the member 20 and move the pressure member I6 toward the fly-wheel I4 against .the action of the springs 22 when the y' Weights`24 move outwardly under the action of V on the weights is dueto this rotation. A clutch plate Y26 is disposed between the pressure plate I6 and .the ily-wheel I and is engaged there- Y between to engage the clutch I3 when the weights 24 are moved outwardly by centrifugal force.

The clutch plate 26 is splined on a sleeve shaft `21 which is rotatably disposed on the intermediate shaft I2l- The shaft 2'I is formed with a sun gear "'28 which forms a part of a planetary gear set 29. The gear s'et comprises also, in addition to the'sun gear 28, a ring gear 3U, a planet gear 3| in mesh with the ring and sun gear and a planet `gear carrier 32.

` The planet gear carrier 32 is splined to the intermediate shaft I2 and also carries a housing portion 33 which constitutes a part of a fluid housing for a fluid coupling device 34. The coupling device 34 comprises an impeller or driving element 35 and a turbine or driven element 36. The driving element 35 is connected with the housing portion 33, and the driven element 36 is connected with the ring gear 30, as shown. The ring gearalso connected with a sleeve shaft 31 rotatably disposed on'Y the' intermediate shaft I2. The, fluid couplingv 34 `is. of the ordinary type in Whiehthe driven element 36 is rotated by the driving element 35 through the medium of fluid in the uid housing `for the vane elements. The iiuid housing for the" fluid coupling is provided with sharp edged orifices or openings 38 in its periphery which permit fluid within the fluidhgusiggte discharge. from the housing for purposes which will be hereinafter described.

A positive type 313 providedA for alternatively connecting the dr enmsliaftI I with the intermediate shaft I2 orwiththe shaft; The clutch 39 comprises a toothed member 40`s`plined onlthe shaftY I'I and adapted to move longitudinally of this shaft to intefengage with a toothed y member 4I splined on the shaft I2 or' with a toothed member 42 splined on the shaft 31. A positive type brale`43 isprovided for valternatively braking the driving element 35 of the fluid coupie 35 and theebytie' planet gear earner' 32 or br'aki'ng'the shaft 31 through a one-way roller brake 44. The brake` 43 comprises a toothed member 35 splined on the stationary casing'431vof the transmission and adapted to move to interengage with a toothed member 41 connected with the driving element 35of the coupling 34 or to interengage with a toothedmember 48 rotatably disposed on the shaft 31. lThe roller brake 44 is disposed between the 'member'48 and the member 42 and preventsA reverse rotation of the member 42 and shaft a'wiientheteth of the members 45 and 48 are inte'reng''aged.,A The member 4,5 has a channeled collar43 fixed on its periphery whereby' it may be 'faeueiy infn/'eel longitudinieuly ofthe transmission as withv use of a fork (not shown), and a member`50 is lcarried bythe member 45 and extends inwardlykintoxa Suitableslot in the member 40, so that when the member 4.5 is' moved, `the member 40 is'l given corresponding movement. The arrangement of the membejsqo and 45 is such that when theniernber 4 5 is'moved to interengage with the member 48j, the'member 4o is simuiteneesly moved to interene'ege with the member 4I; and whenwthe member-'m45 is moved to inter-engage withvthle memberv 41],.the inember 4G is simultaneously moved to intereng'ag'e with `the member 4.2, Theinterconne'ction between the members 40 and 45 thus functions tov assure that when the shaft l2 is' connected with the shaft I I through the elutch 39, the's'haft 31 is braked through the one-way roller brake i44 and the positive brake 43, and th interco'nnection furthermore assures that when the shaft si is eenneeted with fileshare n targuer-fine positive clutch 39, the driving'y element,35p;y the fluidgcoupling 34 is held stationary through the positive biakeas. l u y A Y The tansfissi'niustfetdin Figs; 1 anda provides a lo"A- and a high speed ftio inpflorward save tette-eri 'the sans man n. when the "er as is nevena- ,A l n finden the positive nuten as 'and ,te ytiene the :shaft 31 through tv eloneift/'ay rollerY brake 44j anni threes/nine invebreke' l43, the tiensiiiissio'n conditioned fr forward drive. With neejt the shafts i2 and.

4 the member 45 being so positioned, when the shaft Il) is rotated at a suciently high speed to engage the centrifugal clutchl I3, the shaft 21 is driven through the clutch I3 to drive the sun gear 23, and the planet gear carrier 32 and thereby the shafts I2 and II are driven at a low speed ratio 'through the planetary gear set 29. In this oase the ring gear 3D is held stationary by means ofthe brakes 44 and 43, and the ring gear forms the reaction point Afor the planetary gear set 29.

As the speed of the planet gear carrier 32 increases,I and assuming that the ud coupling 34 ismlled with fluid, driving element 35 of the coupling begins to drive the driven element 36 and thereby the ring gear 35, causing the one-way roller brake 44 to release. The planet gear carrier 32 and thereby the shafts i2 and II are thus rotated at a higher speed than at low speed drive withl the one-way brake 44 engaged.y As the speed of the shaft II increases, the speed of the driven element 36 approaches that of the driving element 35, and the fluid coupling 34 substantially locks up the planetary gear s'et 23 and causes the shaft II to be rotated at substantially the same speed as the shaft Ill. The transmission is'V now in high speed forward drive.

Alheh the member i5 is moved in the opposite direction to connect the shafts 31 and Il through the clutch 39 and to brake the driving element 35 of the coupling 35 by means of the brake Q3, the transmission is conditioned foi1 reverse drive. In this oase, the drive is from the centrifugal clutch I3, which is engaged after the shaft I0 has reached a sufc'ient speed, through the shaft 21 and the planetary gearing 29 to the shafts 31 and I I. VThe planet gear carrier 32 is held stationary by the brake 33, andthe ring gear 35 and thereby the shaft i I are rotated in reverse drive.

The embodiment of the invention shown dia grammatically in Fig. 3 is substantially the same as that shown in Figs. l and 2 with the exception that friction brakes are used in lieii of the positivebrake 43. A` band brake 5I is provided for acting in `congunctior'i with the one-way roller brake for braking the shaft 3i, and a band brake 52 is provided for braking the planet gear carrier 32 through the` driving element 35 of thev fluid coupling 34. A channeled collar 53 is,A provided on the member i5 for allowing easy shifting of this member to position the clutch 39 in eitherI of its two operative positions. This embodiment of the transmission operates in the same manner as the other Iembo'diment with the exception that the'b'ralies 5! and 52 must be engaged and disengaged properly with movement of the member' fil, and this may be done by any suitable means (not shown).

The control arrangement shown diagrammaticaliy in Fig. 4 may be used with either of the above described transmissions. rfhe control arrangement comprises a pump 54 driven by 'the tail shaft Il of either of the transmissions and connected at `its intake side with a sump 55 by a fluid line 55. The pump 5ft is of a fixed displacement type and is connected by the line 55 at its outlet side with theuid coupling 33 in the transmission, and a Avalve 51 is provided in the line 56 effectively between the pump 55s and the fluid coupling. The accelerator 58 for the vehicle in which the transmission is installed,I which is connected with thef'carburetor v59 of the motor of the vehicle, is connected with the valve 51 to operate it. The connectionl with thel valve is such that when the accelerator 53 isV in any of its Vusual operating positions, the pump is effectively 'connected with the fluid `coupling 34 to `provide fluid pressure thereto; however, when the accelerator 58 is moved to its open throttle position at the lowermcst limit of its movement, then the `valve 5'! closes the fluid line between the pump 54 land the fluid coupling 34 to prevent fluid being pumped to the fluid coupling. The discharge orifices er openings 38 in the fluid housing` of the fluid coupling 34 allows the fluid in the housing to discharge therefrom so that the coupling 34 is substantially emptied of fluid on such a closing of the fluid line between the pump and fluid coupling, and there is thereafter no drive through vthe fluid coupling. Thus a depression of the accelerator 58 to its kickdown position functions to empty the fluid coupling 34 and to make it ineffective whereby the driven shaft Il of the transmission is thereafter driven at low speed ratio through the planetary gearing 29 of the It will be seen that the pump 54 acts in conf junction with the orifices 38 to provide means for producing coupling of the uid coupling 34 in accordance with the speed of rotation of one of the shafts in the transmission, in this instance the driven shaft Il. Until the speed of rotation of the driven shaft Il reaches a value such that the pump volumetric output is more than adequate to fill the coupling regardless of the discharge through the orifices 38, the transmission will be in low speed ratio since the fluid supplied by the pump at a 'lower vehicle speed will be immediately discharged through the oriflces so that the coupling will not become effective. 'I'he speed of filling of the coupling 34, after thecritical speed has been reached, is dependent upon the speed of the `pump and, hence, the speed of the driven shaft Il, so that a higher vehicle speed results in faster filling and faster engagement of the coupling. As a result, the pump 44 and the orifices 38 vcoact to provide smooth,

graduated ratio changing upward, which ratio changing is lthereby responsive to the speed of the driven shaft. It will be readily apparent that, when the vehicle is again slowed down below the critical speed, graduated, speed responsive ratio change'downward will occur because the speed of the pump will become inadequate to maintain the coupling filled.

The cooperative effect of the pump 54 and the orifices 38 acts in conjunction with the inherent smooth coupling effect of the fluid coupling 34, as previously described, in order to provide very smooth ratio changes both from low to high and vice versa.

A further inherent beneficial effect is provided by the provision of the driven shaft pump 54 `in conjunction with the fluid coupling 34.l It

is well known that an increase in fluid pressure in a hydrodynamic device will lenable the hydrodynamic device to transfer increased torque without cavitation and consequentv excessive slippage. Thus, when the `couplingis v transmitting torque, an increase in speed of the .driven shaft will cause an increase in output of thepumpto provide an increased pressure inthe coupling due to increased volumetric pump discharge'through the orifices 38. Briefly, since the torque transmitting'capacity of the coupling increases as theY fluid pressure increases, then an increase in pump speed will cause an increased coupling effect,

I wish ittoy be understood that my invention is notto be limited to the specific constructions and arrangements shown and described, except only insofar as the claims may be so limited, as it will be apparent to those skilled in the art that changes may be made without departing from the principles of the invention.

I claim:

' 1.' In a transmission, the combination of a drive shaft, a" driven shaft, a planetary gear set comprising a sun gear, a ring gear, a planet gear in mesh with said sun and ring gears, and a planet gear carrier, a clutch for connecting said drive shaft with said sun gear, a clutch for alternatively connecting said driven shaft with said planet gear carrier or with said ring gear, a oneway brake for said ring gear, a brake for said planet gear carrier, said one-way brake completing a forward drive in a low-speed ratio through said gear set from said drive shaft to said driven shaft when said second named clutch is operative to connect said planet gear carrier and said driven shaft, and a fluid coupling having a driving element connected with said planet gear carrier and having a driven element connected with saidring gear for substantially locking up the gear set and providing a high speed ratio in forward drive between said shafts when said second named clutch is operative to connect said planet gear carrier and said driven Shaft, said brake for said planet gear carrier being effective to provide a reverse drive from said drive "shaft to said driven shaft when said second named clutch is operative to connect said ring gear with said driven shaft.

2. In a transmission, the combination of a drive shaft, a driven shaft, a planetary gear set comprising a sun gear, a ring gear, a planet gear in mesh with said sun and ring gears, and a planet gear carrier, a clutch for connecting said drive shaft with said sun gear, a positive type clutch for alternatively connecting said driven shaft with said planet gear carrier or with said ring gear, a one-way brake for said ring gear, a movable positive brake element for alternatively rendering said one-way brake effective or for braking said planet gear carrier, a fluid coupling having a driving element connected with said planet gear carrier and having a driven element connected with said ring gear, said one-way brake when effective completing a low speed forward drive through said planetary gear set from said drive shaft to said driven shaft and said fluid coupling substantially locking up saidplanetary gear set whereby the one-way brake overruns to provide a high speed forward drive between said shafts when said positive clutch is effective to connect said planetary gear carrier and said driven shaft, said brake element for said planet gear carrier when effective providing a reverse drive from said drive shaft to said driven shaft when said positive clutch is effective to connect said ring gear with said driven shaft, and a control member for simultaneously controlling said brake element and said positive clutch whereby said one-way brake is effective when the positive clutch connects the planet gear carrier with said :driven shaft and whereby said brake element is effective to4 arrest said planet gear carrier when 7 they postiverchitcn connects. said. ringi gearf'and said'v drivenishatt.

3., In' a motor velfiiicle,` the combination of a vehicle motor, an vaccelerator, for said.. motor, a transmission having a drive shaft and. a driven shaft; said 'transmission' includinga planetary gearset adapted to provide a. low speedratio drive between said shattssa one=way brakeior completing said low spe'edirairiot drive and. means adapted to provide;l a? hghspeed ratiddrive betvveerx: said shafts' and-l uid. coupiing vconnected between two of therelement's of said planetary gear set to complete the high speed ratio drive, said fluid coupling havingK a duid outlet .for releasimgf. the: fluidk in' the device, a pumpA driven bysaid driven shaft for supplying. iluid to said fluid. coupling .tonrender it operative, andk a valve under the control of said accelerator for effectively* disconnecting said' i-luid coupling from said pump when the accelerator is moved toward open throttle position whereby the fluid` in said coupli-ng .device drains out through its. said. outlet to render the ilu-id coupling ineiective andtotherehy downshift the transmission from highspeed ratio to low speed ratio.

41.1In a transmission, the combination of a drive shaft, a driven shaft, a. planetary gear set comprising a su-n gear element, a ringigearelement, a planet gear in mesh with. said sun and ring gearelements,- and a planet gear carrierelement, a clutch forl connectingsaid-drive shaft with oneof said elements, a clutch for alternatively 'connecting said driven shaft with a second ora third of said elements, a one-way brake for said second element, a brake ior said third element, said one-way` brake completing a forward drive. in a low speed ratio through said planetary gear set from said drive shat'tozsaid driven shaft Whensa-id second .named clutch is operative to connect said third element and said driven shaft, and a fluid coupling having a driving member connected with said third element and having a driven member connected with said second element for substantially locking up the gear set and providing ahgh speed ratio in forward drive between said shafts when said second-named clutch is operative to connect said third element and said driven shaft, said brake tor, said third element being eieetive. to provide a reverse drive from said drive shaft-to said driven shaft when said second-named clutch is operative to connect saidsecond element with said driven shaft.

y In apower transmission system, the combination of a drivey element, a driven element, means for completing a power train between said elements, and means for' providing graduated completion of said power train in accordance with the. speed of one o said elements, vsaid secondinamed means including a pump driven by said oneelement connected to deliver the pump output to said first named means and means providing a. sharp edged orice in continuous communication with said pump for the relief of said pump output throughout'the completion of said power train.

6'. In a power transmission system, the combination of a drive element, a driven-element, iiuid actuated means for completing a power train between said elements, and means for providing a source of fluid to actuate said first named means- Whose volume increases in ac'- cordance with the speedofone of said elements, said second named' means including ay pump driven by said, one element connected to deliver the .pump output to saidrst namedmeans and means providing al sharp edgednorce in continuous .communication with said 'pump for the relief of said pump output. throughout the completion of: said power train,r said pump being in continuous communication with. said o-rice from the initiation oi movement ot said one element upto the completion of said power train where,- by the initiation. tif-completion of said power trai-nis responsivev to the speed of said one element.

7. In a power transmission system, the combination of a driveelement, a. driven element, means providing aI power train between said elements and including a hydrodynamicdevice for completing the power train, and means for providing a graduated pressure on said h-ydrodynamic device inaccordance with the speed of said. driven element, said, last mentioned means including. Aa positive displacement pump driven by one of said elements and arranged to provide ak pump; output which, increases with increase in speed of vsaid one element, said pump being connected to deiiver the pump' output to said hydrodynamic device.`

d. In a power transmissionsystem, the combination of a. drive element, a driven element, means providing a power train between said elements and including aY hydrodynamic device for completing the power train, and means for pro viding a graduatedfluidpressure. on said hydrodynamic devicel in accordance with the speed of said driven' element; said last mentioned means including a pump driven :by one ofY said. elements connected to deliverV the pump: output to said 9. In a power transmission system, the combination of a drive. shaft, a driven. shaft, means providing a power train between said shafts and including a hydrodynamic device having a drive element and a driven element for completing the power train, said hydrodynamic device having one of saidy elements connected to rotate with one of said shafts, and a. pump driven by said one shat connected to deliver the pump output to said hydrodynamic device, said one element andsaid pump as they increase in speed with saidone shaft providing increased coupling of said hydrodynamic device as the speed of said one shaftvincreases.

10i In a power transmission system, the combination of adrivo shaft, a driven shaft, means providing a power train between said shafts and including ahydrodynamic device having a drive element and a driven element for completing the power train, said hydrodynamic device havingone oirsaid elements connected to rotate with one of said shafts, a pump driven by said one shaft connected to deliver the pump output to said hydrodynamic device, and means providing a restricted orifice for the relief of said pump output, said one element andsaid pump relieved in pressure by said orifice as the element and pump increase in speed providing increased coupling of said hydrodynamic device as the speed of said'one shaft increases.

11. In power transmission mechanism, the combination of a drive shaft, a driven shaft, means for providing low and high speed drives between saidshafts, means'subject to changes in fluid volumetric output for changing the drive from saidlow` speed driveto said high speed drive in response to increases in uid volumetric outputv and for changingthe drive from said high speed drive back again to said low speed drive in response to decreasesin fluid volumetric output, a pump for supplying fluid and having a fluid outlet and driven by one of said shafts, means forming an orifice continuously connected with the outlet of said pump in both of said speed drives for relieving the fluid output supplied by said pump, and means for connecting the outlet of said pump with said drive changing means whereby the drive changing means causes a change from said low speed drive kto said high speed drive in response to an increase in fluid volumetric output onincreasing speed of said one shaft and causes a change back again from said high speed drive to said low speed drive in response to a decrease in fluid volumetric output on decreasing speeds of said one shaft.

12. In power transmission mechanism,v the combination of a drive shaft, a driven shaft, means for providing low and high speed drives between said shafts, means subject to changes in fluid volumetric output for changing the drive from said low speed drive to said high speed drive in response to increases in fluid volumetric output and for changing the drive from said high speedpdrive back again to said low speed drive in response to decreases in fluid volumetric output, a xed displacement pump for supply-` ing fluid and having a fluid inlet and a fluid outlet and driven by said driven shaft, means forming a fluid sump with which said inlet is oonnected, .means forming an orifice continuously connected with the outlet of said pump in both of said speed drives and adapted to discharge into said sump for relieving the iluid output supplied by said pump and to decrease with decreases in speed of said driven shaft, and means for connecting the outlet of said pump with said drive changing means whereby the drive changing means causes a change from said low speed drive to said high speed drive in response to an increase in fluid volumetric output on increasing speeds oi said driven. shaft and causes a change bacia again from said high speed drive to said low speed drive in response to a decrease in fluid volumetric output on decreasing speeds of said driven shaft.

i3. In power transmission mechanism, the combination of a drive shaft, a driven shaft, means for providing low and high speed drives between said shafts, means subject to changes in fluid volumetric output for changing the drive from said lovv speed drive to said high speed drive in response to increases in fluid volumetric output and for changing the drive from said high speed drive back again to said low speed drive in response to decreases in fluid volumetric output, a pump for supplying fluid and having a fluid outlet and driven by one of said shafts, means forming an orice having sharp edges and continuously connected with the outlet of said pump in both of said speed drives for allow'- ing iiuid supplied by said pump to discharge therethrough, and means for connecting the outlet of said pump with said drive changingmeans whereby the drive changing means causes a change from said low speed drive to said high speed drive in response to an increase in fluid output on increasing speeds of said one shaft and causes a change back again fromsaid high speed drive to said low speed drive in response `to a decrease in fluid output on decreasing speeds of said one shaft. i

le. In power transmission mechanism, the combination of a drive shaft, a driven shaft, means for providing low and high speed drives betweenl said shafts and including a planetary gear set, means subject to changes in fluid volumetric output for changing the drive from said low speed drive to said high speed drive in response toV increases in fluid volumetric output and for changing the drive from said high speed drive back again to said low speed drive in response to decreases in fluid volumetric output, a` pump for supplying fluid and having a fluid outlet and driven by said driven shaft, means forming an orifice continuously connected with the outlet of said pump in both of said speed drives for relieving the fluid output supplied by said pump, and means for connecting the outlet of said pump withsaid drive changing means whereby the drive `changing means causes a change from said low speed drive to said high speed drive in response to an increase in fluid volumetric output on increasing speeds of said driven shaft and causes a change back again from said high speed drive to a low speed drive in response tc said decrease in fluid volumetric output on decreasing speeds of said driven shaft.

15. In an automotive vehicle having a driving motor, the combination of a throttle control for said motor, a drive shaft adapted to be driven by the driving motor, a driven shaft adapted to drive the vehicle, means for providing low and high speed drives between said shafts and including a planetary gear set, means subject to changes in` fluid volumetric output for changing the drive from said low speed drive to said high speed drive in response to increases in fluid volumetric output and for changing the drive from said high speed drive back again to said low speed drive in response to decreases in fluid volumetric output, a pump for supplying fluid and having a fluid outlet and driven by said driven shaft, Vmeans forming an orifice continuously connected with the outlet of said pump in both of said speed drives for relieving the fluid output supplied by said pump, means for connecting the outlet of'said pump with said drive changing means Wherebythe drive changing` means causes a changefrom said low speed drive to said high speed drive in response to an increase in fluid volumetric outputon increasing speeds of said driven shaft and causes a change back' again from said vhigh speed drive to said low speed drive in response to a decrease in fluid volumetric output on decreasing speeds of lsaid driven shaft, and means including a valve under the control of'said throttle control for causing" a change from said high speed drive to said low speed drive when said throttle control is movedtoward openthrottle position.

16 In an automotive vehicle having a driving motor, the combination of a throttle control for said motor, a driveshaft adapted to be driven by the driving motona driven shaft adapted to drivew the vehicle, means for providing low and high speed drives between said shafts, means subject to changes in fluid volumetric output for changing the drive from said low speed drive to said high speed drive in response to increases in fluid volumetric output and for changing the drive from said high speed drive back again to said low speed drive in response to decreases in fluid volumetric output, a pump for supplying fluid and havingv a fluid outlet and driven by one of said shafts, means forming an orifice continuously connected with the outlet of said pump in both of said speed drives for relieving the iluid output'supplied by said pump, means for connecting the outlet of said pump with said drive changing means whereby the drive changinglmeans causes a change :from'said low speed drive to said high speed drive in'responseto an increase in fluid volumetric outputon increasing speed of said vone shaft and causes .a change baclragain Yfrom said Thigh speed drive to said low speed vdrive in response to a decrease fluid volumetric .output on decreasing speeds of said one shaft, and means under thecontrol of 'said throttle control for causing a change .'fromsaid high speed drive to said .low speed drive when saidthrottlecontrol isA moved' toward open .throttle position.

17. In a transmission, the 'combination of a drive shaft, a driven shaft, means for providing a plurality of drive'ratios between said shafts, fluid actuated means including a hydro-dynamic device adapted for changing vthe drive 'through the'transmission from one of said drive. ratios .to a second drive ratio, means effective on said hydrodynamic' devicev for causing '.achange 'in speed. ratio at a time when one of saidshafts reaches a predetermined speed and for causing graduated Ycompletion of said second drive ratio in accordance With thespeed of said one shaft, said third named means including a' pump driven by said'one shaft connected for delivering. the pump output to. said Vhydrodynamic 1device,;a'nd a'singl'e orice for controlling the relief of .the pump output.

18. In'a transmission, the combination of 'a drive shaft, a driven Shaft'means for Vproviding alplurality of drive ratios between said shafts, uidactuated means adapted for changing the drive through the transmission from'one of said drive ratios'to a second drive ratio, and means effectiveon said fluid actuated means'for causing a change in speedrati'o at a time' when said driven shaft reaches 'a predetermined speed `and for causing graduated completion of said second drive ratio in accordance with the speed of said `driven shaft, said third named means including apositive displacement'pump driven by said driven shaft connected for delivering the pump output to said uid actuated 'means and means-providing a sharp edged orifice for vcontinuously relieving saidpump output in `all 'of said: drive ratios.

1'9.. In avtransmission, the combination `of `a drive shaft,l a driven shaft, means for providing a plurality'of power trains 'between saidshafts and including a. hydrodynamicr device, said hydrodynamic device'having a drive element and a driven element with one. of said elements adapted for being ccnnectedtorotate with one of said shafts, and a positive: displacement pump driven; by said one shaft and arranged to provide aA pumipQutput-which increases with increasefin speed of said one shaft, said pump being connectedfor delivering the pump output-to'said hydrodynamic device, said element. and said pump providing increased coupling of said hydrodynamic device as the speed ofsaid oneshaft increases.

V20..,'In an automotive vehicle having a; driving moton'the combination. of a throttle control for. said motor, a drive shaft adapted to be-'driven by the driving motor, a driven shaft adaptedto drivethe'vehicle, means for providing a plurality of power trains between saidshafts andV including va hydrodynamic device, said `hydrodynamic device .having a drive velement and a. driven velement with one of said elements adapted for being secured; to one of said'.l shafts, a. positive. dis.- placementpump driven bysaid one. shaft and arranged to provide a pump output which in.-

CII

creases withincrease vin speed. of isaidfone shaft, said :pump 'being connected -for delivering the pump output: to said hydrodynamic device, said one element and said'pump providing increased coupling of said'hydrodynamic device as the speed of vsaid one shaft'increases; and means-under the control of said vthrottle control for causing a change toanother power train when said-throttle control is moved toward open throttle position.

2.1. In a transmission, the combination of a drive shafts, driven shaft, means for providing a low speed drive ratio-anda high-speed drive ratio between said shafts, vmeans Vfor changing the drive through the transmission from one of said drive ratios tothe othenand means effective on'sad drive changing means for causing a change in speedratio according to the change in speed ofzone of' said shafts and for causing graduated drive changing lcompletion by said drive changing meansin accordance with the speed of said one shaft, said third named means including apump driven by said one shaft connected for delivering the pump output to said drive changing means and means providing .a sharp edged orice'for continuously relieving said pump output inall. of said drivezratios.

l22.In a transmission, vthe .combination of a drive shaft, adriven' shaft, means for providing aplurality of drive ratios between said shafts, said means including a gear'set for providing a relatively low speed drive and coupling means for coupling'two elements ofsaid gear set to provide a relatively high speed drive, and means Aeffective on saidl coupling means for causing coupling thereof to effect a 'change in speel ratio from said low speed drive to said high speed drive at a time when one of saidshafts reaches a-predetermined speed and for causing coupling of said coupling means in a. graduated manner in accordance With tlrespeed of said one shaft, said third'named means including a pump driven by said one'shaft adapted for delivering the pump output'to Asaid coupling means and means providing afrestricted -ori'ce'for the discharge of said pump output.

23. In atransmission, `the combination of a drive'shaft; a kdriven shaft, means independently operable toprovide a lovvspeed ratio between said shaftsan'd a`hydrodynamic device operable in conjunction Withsaid first named means to providea high speedvratio between said shafts, a pump'driveni by said .driven shaft for supplying duid to said hydrodynamic device, and means providing a restricted orifice for continuously relievhig'the'outpirt from said :pump whereby said hydrodynamic device is rendered effective in accordance Withthespeed of said driven shaft, said pump andfsaidorificebeing arranged to render said hydrodynamic device ineffective when the speedof 'said .driven shaft falls below'a predeterminedspeed to=.c,a.use;.afchange toy alower speed ratio,

'24.. In. an 'automotive vehicle 1a; driving motor', thecomloinationrofa throttle control for said motor, .a drive .shaftadaptedito be driven by the .driving motor, `wa. driven shaft adapted to drive the vehicle, means independently operable to provide a `lmivspeed: ratio between said shafts and fluid actuated means operable in conjunction with said first-named'means to provide a high speed ratio between said shafts, a pump driven by said shaft forsupplying fluid to said second: named'means, means "providing a sharp edgedorifice forzcontiinuously relieving the outputifrom: saidipumpk in. .all of said. speed ratios whereby said secondnamed means arerendered effective in accordance with the speed of said.

driven shaft, said pump and said orice being arranged to render said second named means in effective when the speed of `said'driven shaft falls belowa predetermined. speed to cause a change to said lower speed ratio, and means under the control of said throttle control for causing a change from said high speed ratio to ,said low speed ratio when said throttle control is moved toward open throttle position.

25. In a motor vehicle, the combination 4of a vehiclemotor, an accelerator for said motor, a transmission having a drive shaft and a driven shaft, said transmission including gear ,means providing a low speed ratiopdrive Vbetween said shafts, means adapted 'to provide a high speed ratio drive between said shafts and including a hydrodynamic coupling device for completing said highspeed ratio drivegand having arestricted fluid outlet for the release of iuidin the coupling device, a source of fluid pressure operatively associated with one of said shafts for supplying fluid to the coupling device at a, rate increasing with the speed of said oneshaft for rendering the coupling device operative whereby ratio changing from said low speed drive to 'said high speed drive is effected responsive to the speed of said one shaft, and means under the control of said accelerator for effectively disconnecting the source of fluid pressure from said coupling device when said accelerator is moved toward open throttle position whereby the uid insaid coupling device.

drains out through its said outlet to render the coupling device inoperative and to thereby down shift the transmission from high speed ratio to low speed ration' v i 26. In a motor Vvehicle-*the'combination ofra` vehicle motor, an accelerator for said` motor, a transmission VhavingV a ,-drivevshaft and a driven shaft,-said` transmission includingfgear means providing a low speed rratio drive between saidY shafts and means adapted to provide a -high speed ratio drive `between said shafts and including a hydrodynamic coupling device for completing the high speed ratio drive, said coupling device.

having an outlet therein for releasing fluid in the device, a -pump driven by one of saidshafts for supplying fluid to said device vat a rate increas-v ing with the speed of said one shaft to render the coupling deviceoperative fwhereby `ratio changing from said low speed drive `to said high speed drive is effected responsiveto the-speed of said one shaft, and a valve under the-control of said accelerator for stopping the flow of liuid to said coupling device when said accelerator is movedtoward openthrottle position whereby the fluid in said -coupling device drains out through its said outlet to render the coupling device inoperative and to thereby downshift the transmission from-high speed ratio to low speed ratio., f Y

' 27. In a motor vehicle, the combination of a vehicle motor, an accelerator for said motor, a transmission havingv a drive shaft and a driven shaft,V said transmissionv including gear means providing a vlow speed ratio positive drive between said shafts andmeansproviding a high speed ratio between said shafts, said last named means including a hydrodynamic couplingfdevice, means including a source `of fluidi' pressure operatively associated with oneA of said shafts for supplying fluid to the hydrodynamic device at a rate increasing with the speedrof said one shaft for `rendering the hydrodynamicdevice operative toftherebycause a downshiftv of the transmission.

from highspeed ratiotov low speed ratio.

28. In a motor vehicle, the combination of a vehicle motor, an accelerator for said motor, aA

transmission having .a drive shaft and a driven shaft,l said transmission comprising a planetary gear set including a sun gear element, a ringj gear element, a, planet gear element in mesh with` saidtwo elements, and a planet gear carrierelement, said drive shaft being adapted to drive one of ,said gear elements and a second of said gear.v

elements being adapted to drive said driven shaft, a one-waybrake for` the third of said gear .ele-1 ments forcompleting-adrive in a low speed ratio through saidlgear set from said drive shaft toA said driven shaft, a hydrodynamic coupling device` connected between said second andV third elements of the planetary gear set for substan-,

tially locking up the gear set and providing a high speed ratio between: said shafts, meansincluding a source of fluid pressure operatively asso-` ciatedwith one of said shafts'for supplying fluid to the hydrodynamicy device at a rate increasing with-the-speed of said one shaft forlrendering` the hydrodynamic device operative lwhereby ratio changingv from said low speed ratio to said high speed ratio is effected responsive to the speed of said one shaft, and means, including'amernber i under vthe control of the accelerator, for rendering saiddeviceineffective when the accelerator` is moved toward open throttle position and 'to thereby downshift the transmission from `high speed ratio to -low speed ratio.` i f 29. In a motor vehicle, the combination of a` vehicle motor, an accelerator for saidl motor,- a transmission having a drive shaft and a driven shaft, said transmission comprising a planetary gear set including a sun gear element, airing gear element, a planet gear element in mesh with said two elements, `and a planet gear carrier element, said drive shaft being adapted to drive one of said gear elements and a second of said gearelements.

being adaptedV to drive said driven shaft, avone-; way-"brake-for a third of said gear elements for completing a positive drive in a low speed ratio through said gear set from said drive shaft to said driven shaft, a hydrodynamiccoupling deviceI connected between-said second and third elements ofthe planetary gear` set for substantially locking up the gear set and providing a high speed ratio between said shafts, means including a pump driven bysaid drivenfshaftfor supplying iiuid to the hydrodynamic device at a rate increasing with the speed of saiddriven shaft for rendering thelhydrodynamic device operative whereby ratio changing between said lowA ratio and said high ratio is effected responsive to the speed ofthe driven shaft, and means, including a member under the control of the accelerator, for rendering said hydrodynamic coupling` device ineifective and .to thereby downshift the Atransmission from high speed ratio vtolow speed ratio. e I

30. In a motor vehicle, Athe combination of a vehicle motor, an accelerator for said motor,'a

transmission having a drivev shaft and a Adriven shaft, said transmission including a planetary gear set adapted to provide a ,low sped ratio'positive drive between said shafts, a one-way brake for completing said low speed ratio drive,- meansV adapted .tolpro-vide a high speedratic drive be? twecnlsaid shafts and includinga fluid coupling device connected between two of theelements .of said planetary gear set to complete the high speed ratio drive, means including a pumpzdriven by one of*` said shafts for supplying fiuidto the coupling device for rendering it operative whereby ratio changing between said low speed drive and said high speed drive is effected responsive tothe speed of said one shaft, and means under the control of said accelerator for rendering said device ineiective and to thereby downshift Vthe transmission fromhigh speed ratio tolow speed ratio.

'31. In a motor vehicle, the combination of a vehicle'motor, anaccelerator for said motor, a transmission having a drive shaft and a driven shaft, means connected between said shafts and adapted to provide a low speed ratio positive drive,

means including said first-named means `anda` hydrodynamic coupling. device connected there# toadapted to provide a high sped ratiobetween said. shafts, means including a positive displacement pump. driven by said driven; shaft for supplyinguid to the hydrodynamic device for ren# dering it operative Vwhereby ratio .changing between the low speed ratio. and the high speed ratiois effected responsive to the speed oi said driven shaft, and means under the control of said accelerator` for rendering said device ineffective and to therebyv downshift vthe transmission from high speed ratio to low speed ratio.

-32.'In a motor kvelnclethe combination of a vehicle motor, an acceleratori for said motor', a transmission having' a drive shaft and a driven shaft, said transmission comprising means pro# viding a loW' speed ratio between said shaftsv and means adapted to provide a high speed ratio between said shafts, one of said means including a hydrodynamic couplingdevice, the' othero'i 4said means' providing a positive drivameans including a source of'uid pressure operatively associated with one of: said shafts for supplying 'fiuid to' the hydrodynamicy device at a rate increasing `with the speed of said one shaft for renderingthe. de# vice operative lwhereby ratio changingbetween said. low ratio and said` high ratio is .effected responsive to the speed of said one shaft, and means under the control of said accelerator for 'rendering. said'hydrodynamic device-ineiiective when said accelerator is given an'v operative stroke to therebyshiit the transmission from one Aspeed ratioto the other .speed ratio.

33. In' a motor vehicle, the combination of .a vehiclemoton. an accelerator for said motor,^a transmission having a drive shaft and a driven shaft, said transmission comprising means provi-ding'a' lowl speed ratio between said shafts and' means adaptedto provide-a high speed ratio between said shafts, one of said means` including a hydrodynamic coupling device, the other oi'- said means comprising'essentially gearing and providlnga positive drive, means including a positive displacement pump'driven by said dri-ven shaft for` supplying fluid to the hydrodynamic device for rendering 'it operative whereby ratio changing from said low ratio to said high ratio is effected responsive to the' speed of said one shaft, and

Y means under the control of said accelerator for rendering said hydrodynamic device Yeffective when said accelerator is givenan operative stroke to thereby shift the transmission from one speed ratio' 'tothe' other'speed ratio.

In'a power transmission Wstem, the combination ofay drive element, a dri-veri element,

means'forcompieting ay power train between said elements, land means for providing .graduated completion'of said power train in accordance withthe speedof saidy driven element, said second named means including a positive displacement pump driven by said driven element and arranged to providea pump output which increaseswith increase in speed of said driven ele'- ment, said pumpbeing connected to deliver the pump output to said 'rst named. means, said second named means further including means providing a sharp edged orice in continuous communication .with saidpump for therelief oi said pump outputv throughout the'completion of said power train.

35. In a power transmission system, the combination .of a drive element, a driven element, fluid pressure responsive meansl for completing a power train between said elements, and means for` providing a'luid pressure to said rst named means that increases in accordance with the speed of said driven element, said second named means including a positive displacement pump driven by said driven element and arranged to provide a pump output which increased` with increase inA speed of said driven element, said pump being connected to deliver the pump output to said first named means, said second named means further including means providing a sharp edged orice for the-'relief of. said pump output, said pump'being in continuous communication with said orice from the initiation of movement of said driven element vupf to the completion of said power trainv whereby the completion of said power train is responsive to the speed of said driven element.

36. In a power transmission system, the combination of a drive'shaft, a driven shaft, means providing a power trainbetween said shafts and including a hydrodynamic device having a drive element and a drivenelement for completing the power train, saidhydr'o'dynamic device having one .of said elements connected to Vrotate with one of said shafts,` and a positive displacement pump driven` by said oneshaft and arranged to provide a pum-p output which increases with increase in speed of Said one elem-ent, said pump being connected to deliver the pump output to said hydrodynamic device, said one element and said pump as they increase in speed with said one shaft providing increased coupling of said hydrodynamic device as the speed of said one shaft increases.`

DONALDA W. KELBEL.

References Cited .in the 'iile of this patent UNITED STATES'r PATENTS Number Name v Date 2,014,944 Martyrer Sept. 17, 1935 2,018,616 Martyrer Oct. 22, 1935 2,024,842 -Bauer -Dec. 17, 1935 2,063,471 Stedeeld Dec. 8, 1936 2,081,863 `Dufield May 25, 1937 2,131,619 Duilield Sept. 27, 1938 2,150,151 Burrows Mar. 14, 1939 2,224,884 Schneidcr Dec. 17, 1940 2,301,451 Pollard Nov. 10, 1942 2,312,849 Pollard Mar. 2, 1943 2,314,554 Penningtonl Mar. 23, 1943 2,352,004 Pollard Y June 20, 1944 2,377,851 Blank f June l2, 1945 June 18, Mar. 9, 

